TP 428 
•.S3 U6 
Copy 1 



REPORT 

) 

MECHANICAL TESTS 

i.)F THE 

Potomac Red Sandstone 
Company's Stone 



MADE WITH THE 



U. S. TESTING MACHINE 



Wa rtown Arsenal, Mass. 



DECEMBER nth, i8 



WASHINGTON, D. C. 
GiHsr Bkos., Pkintkks^xi) Book bin' drks. ^ 



F 



"iii| 



► 



(Copy.) 
ORDNANCE DEPARTMENT, U. S. A. 



REPORT 



MECHANICAL TESTS 

MADE WITH THE 

U. S. TESTING MACHINE, 

Capacity, 800,000 Pounds, ; 

AT 

WATEETOWJSf ARSENAL, MASS. 

December 11th, 1883, 

FOE 

H. H. DODGE, 

WASHINGTON, D. C. 



Testis by Compkession. 
TEN PIECES POTOMAC RED SANDSTONE COMPANY'S STONE. 






3267 
3268 
3269 
3270 
3271 
3272 
3273 
3274 
3275 
3276 



Color of 
Specimen. 



Nominal Dimen- 
sions. 



Light red. .| 6" cube. 

do do.... 

do do.... 

Dark red... do.... 



Weight. 


Weight 
per Cu- 
bic ft. 


Lbs. 


Oz. 


19 


6 


lbs. 
155 


1? 


4 


154 


20 


4 


16U 






Actual Dimekhioxbw 



Length. 



20 



16U 



do... 

do [ do 

do 6" X 6" X 12" 

do 6" X 6" X 18" 

Light red.. 6" x 6" x 18" 
Dark red... 6" x 6" x 24" 



...do 19 :12 158f 



4 


162 





159{ 


8 


156 


8 


155i 


4 


1601 



5.99 

6.01 

6.01 

5.99 

6.00 

6.00 

12.00 

18.02 

18.03 

24.00 



Compresaed 
surface. 



6.01 
6.00 
6.00 
601 
5.99 



6.00 
5.99 
6.0i 
6.02 
5.98 



I 

6.00 6.00 

6.01 ; 6.02 
5.97 6.02 

6.00 j 6.02 

6.01 i '6.00 



The light- red specimens showed before testing distinct stratification. 
The bed faces of the dark-red specimens could not be identified : 
apply the compression loads. 

(Signed) Correct: J. E. Howabd. 



1 

„ ^. Load 
Section- 


Ultimate 
Strength. 


Remarks. 




al Area.. ^!"''"f 
1st crack. 


Total Lbs. 


Lbs. per 
Cub. in. 




D" 1 










36.06 580,000 


599,500 


16.625 h 

1 




35.94 : 670,000 


670,000 


18.642 


5^ Tested on "bed." 




36.06 797,000 797,000 


22.102 


J 




36.18 354,000 726,700 


20.086 


One compressed fuce ' 


'.01^ convex. 


35.82 620,000 


663,500 


18.523 






36.00 550,000 


714,500 


19.847 1 One compressed face ' 


',01^ convex. 


36.18 600,000 


708,000 


19.569 






35 94 600,000 651,000 


18.114 






36.12 ' 680,000 702,000 


19.435 Tested on "end." 




36.06 670,000 ; 675,900 i 18.744 

1 1 i 





consequently the best dressed faces were selected against which to 



DETAILS OF TESTS OF PRISMS. 



No. 3,273. 

Nominal Dimensions, 12" x 6" x 6". Actual Dimensions: Length. 12" 

Sectional Area, 6.01" x 6.02"=3G.18 Cubic Inches. 

Gauged Length, 10". 



Applied Loads. 



Total 
Lbs. 



5,000 
10,000 
20,000 
40,000 
80,000 
100,000 

5,000 
100,000 
140,000 
180,000 
200,000 

5,000 
200,000 
240,000 
280,000 
300,000 

5,000 
300,000 
340,000 
380,000 
400.000 

5,000 
400,000 
440,000^ 
480,000 
500,000 

5,000 
500.000 
540,000 
.580,000 
600,000 

5,000 
600,000 

708,000 



Lbs. 

per Cubic 

Inch. 



In Gauged 
Length. 



.0 

.0005 

.0017 

.0020 

.0035 

.0050 



.0050 
.0072 
.0098 
.0110 



Set, 
Inches. 



.0010 



.0110 
.0132 ; 
.0155 ! 
.0170 I 



I .0015 



I .0170 i 

! .0190 i 

.0215 ' 

1 .0228 I 



0022 



.0230 
.0250 
.0278 
.0287 



.0290 
.0312 
.0335 
.0350 



.0025 



.0352 i 



19,569 



Deflections at 
Middle, Inches 



Hori- 
zontaL 



Cracked at corner of 

compressed face. 
Ultimate strength. 



Opened oblique longitudinal seams. 

(Signed) Correct : J. E. Howard. 



No. 3,274. 

Nominal Dimensions, 18" x 6" x 6". Actual Dimensions : Length, 

18.02" Sectional Area, 5.97" x 6.02"=35.94 Ciibic Inches. 

Gauged Length, 15" 



Applied Loads. 



Total 
Lbs. 



5,000 
10,000 
20,000 
40.000 
80,000 
100,000 

5,000 
100,000 
140,000 
180,000 
200,000 

5,000 
200,000 
240,000 
280,000 
300,000 

5,000 
300,000 
340,000 
380,000 
400,000 

5,000 
400,000 
440,000 
480,000 
500,000 

5.000 
500,000 
540,000 
580.000 
600,000 

5,000 
600,000 



In Gauged 
Length. 



per Cubic \ pres'ion 
Inch. I Inches. 



.0 

.0002 
I .0009 
! .0025 
I .0070 
i .0090 



651,000 18,114 



' .0092 

i .0130 

.0170 

I .0185 



.0185 
.0220 
.0260 
.0278 



,0280 
0310 
0350 
0368 



.0370 
.0402 
.0442 
.0460 



.0465 

.0502 

.0545 

i .0570 



Set, 
Inches. 



.0015 



.0580 



.0027 



.0032 



.0040 



.0047 



Deflections at 
Middle, Inches 



Hori- Vertical 
zontal. 



Slight crushing at one 

compression face. 
Ultimate strength. 



Burst into fragments suddenly under the maximum pressure, with 
a loud report. 

The two principal fragments were pyramidal-shaped, approxi- 
mately, their bases being the compressed faces of the prism. 

(Signed) Correct : J. E. Howard. 



No. 3,275. 

Nominal Dimensions, 18" x 6" x 6". Actual Dimen.sions : Length, 

18.03". Sectional Area, fi.OO" x G.02"=36.12 Cubic Inches. 

Gauged Length, 15". 



Applied Loads. 


In Oatjoed 
Length. 


Deflections at 
Middle, Inches 




Total 
Lbs. 


Lbs. 

per Cubic 

Inch. 


Com^ 
pres'ion 
Inches. 


Set, 
Inches. 


Hori- 
zontal. 


Vertical 


Remarks. 


5,000 
10.000 




.0 

.0003 

.0012 

.0038 

.0085 

.0105 


.0020 
.0029 
.0032 
.0040 
.0045 
.0050 


' 






20 000 






40,000 






80,000 

100,000 

5,000 










100,000 
140,000 
180,000 
200 000 




.0108 
.0145 
.0182 
.0200 
















5,000 






200,000 




.0200 
.0235 
.0270 
.0285 




240,000 






280,000 
300,000 










5,000 






300,000 
340,000 
380,000 




.0288 
0318 






.0350 
.0365 




400,000 
5,000 










400,000 




.0368 
.0395 
.0430 
.0447 




440,000 

480,000 

500,000 

5,000 


















500,000 
540,000 




.0450 
.0481 
0520 








580,000 






600,000 
5,000 




.0535 




600,000 
680,000 


0538 




702,000 


19,435 










Ultimate strength. 













Fractured suddenly, with a loud report. 

Warning of impending fracture occurred about two seconds be- 
foi'e the report was beard. 

Lines of fracture were parallel to the grain of the stone. There 
were two pyramidal fragments having steep sides. 
(Signed) Correct: J. E. Howard. 



No. 3,276. 

Nominal Dimensions, 24" x 6" x 6". Actual Dimensions : Length, 

24.00". Sectional Area, 6.01" x 6.00"=36.06 Cubic Inches. 

Gauged Length, 20". 



Applied Loads. 


In Gauged 
Length. 


Deflections at 
Middle, Inches 




Total 
Lbs. 


Lbs. 

per Cubic 

Inch. 


Com- 
pres'ion 
Inches. 


Set, 
Inches. 


Hori- 
zontal. 


Vertical 


Kemakks. 


5,000 
10,000 
20,000 
40,000 




.0 

.0010 

.0022 

.0050 

.0100 

.0122 


.0018 
.0028 
.0035 
.0042 
.0052 






• 














80,000 






100,000 
5,000 






100,000 
140 000 




.0125 
.0172 
.0220 
.0242 








180,000 

200,000 

5 000 














200,000 
240,000 




.0245 
.0290 
.0335 
.0360 








280 000 






300,000 

5,000 

300 000 












.0362 
.0408 
.0455 
.0480 




340,000 
380,000 
400,000 














5,000 






400,000 
440 000 




.0482 
.0530 
.0580 
.0605 








480,000 

500,000 

5,000 

500,000 
















.0610 
.0662 




540,000 
670,000 
675,900 








Cracked. 


18,744 










Ultimate strength. 











Fractured suddenly with a loud report. 

The principal fragments showed lines of fracture extending 
lengthwise the prism ; also fractures square across parts of the pieces. 



R E: ?vl A R K S . 



The specimens were tested between flat steel platforms. 

Compression measurements and sets were determined by securing 
a micrometer to the prisms ; the instrument covering the gauged 
length. Contact with the si^ecimens being made with the conical 
steel points of the micrometer. 

This instrument was removed before the close of the test to avoid 
injury. 

(Signed) Correct: J. E. Howard. 

(Signed) F. H. PARKER, 

Major of Ordnance, Commanding. 



LIBRARY OF CONGRESS 

llilllllllllllllillll' 

029 965 525 8 



